Hand and Arm Prosthesis Uses a Variety of Control Techniques

Duplicating the functionality of the human body — or even parts of it — if an enormous task. That doesn’t mean that many haven’t tried…

Duplicating the functionality of the human body — or even parts of it — is an enormous task. That doesn’t mean that many haven’t tried, and while not perfect, prostheses in various forms make life better for a wide range of people. To help a person with a congenital limb deficiency in his country, Nguyễn Phương Duy has created a transhumeral (above the elbow) prosthesis that features 10 degrees of freedom (DOF). Control options — using a Raspberry Pi and several Arduinos — include computer vision (CV), brain-computer-interface (BCI), and electromyography (EMG).

The device can operate each finger independently, along with a 2DOF thumb. The wrist rotates back and forth, and can tilt forwards and backwards as well, and the hand can even make a sort of waving motion, swaying left and right.

The hand can be programmed to move to several pre-set positions, and a brain-computer interface is demonstrated for control. Furthermore, the system can use CV capabilities to focus on an item, then adjust itself appropriately for the situation — e.g. if it sees a bottle, it might adjust its grip to be able to pick it up, and can even aim the gripper in that direction. A potential EMG interface for this type of device is shown in the second video.

Though it appears to still be somewhat of a prototype, we’re excited to see how this prosthesis continue to advance. Hopefully it will help the person it was intended for manipulate objects more easily, and perhaps others in the future too!